Contribution of endogenous G-protein-coupled receptor kinases to Ser129 phosphorylation of alpha-synuclein in HEK293 cells.

The majority of alpha-synuclein (alphaS) deposited in Lewy bodies, the pathological hallmark of Parkinson's disease (PD), is phosphorylated at serine 129 (Ser129). Ser129 phosphorylation of alphaS has been demonstrated to enhance the alphaS toxicity to dopaminergic neurons in a Drosophila model of PD. Phosphorylation of alphaS at Ser129 seems to play a crucial role in the pathogenesis of PD. Here, we assessed the contribution of ubiquitously expressing members of the G-protein-coupled receptor kinase family (GRK2, GRK3, GRK5, and GRK6) to Ser129 phosphorylation of alphaS in HEK293 cells. To selectively reduce the endogenous expression of each member of the GRK family in cells, we used small interfering RNAs. Knockdown of GRK3 or GRK6 significantly decreased Ser129 phosphorylation of alphaS; however, knockdown of GRK2 or GRK5 did not decrease alphaS phosphorylation. The results indicate that endogenous GRK3 and GRK6, but not GRK2 or GRK5, contribute to Ser129 phosphorylation of alphaS in HEK293 cells.

Asymptomatic ventriculomegaly with features of idiopathic normal pressure hydrocephalus on MRI (AVIM) in the elderly: a prospective study in a Japanese population.

We investigated if there are individuals at a preclinical stage of idiopathic normal pressure hydrocephalus (iNPH) in a general population. All the residents (n=1142) aged 61 years (n=306, men/women=156/150) and 70-72 years (n=836, men/women=356/480) in the two communities of Japan were requested to take brain MRI examination. The "iNPH features on MRI" were defined as an Evans index of >0.3 and a narrowing of the subarachnoid space and cortical sulci at the high convexity of the cerebrum. "Possible iNPH" was defined as the presence of one or more symptoms of iNPH, together with such MRI features. 790 (69.2%) of the 1142 residents participated in this study. Among them, 51 individuals (men/women=35/16) (6.46%) had the enlarged ventricles (Evans index of >0.3), 12 (men/women=7/5) (1.52%) of which showed the iNPH features on MRI. Of the 12 individuals, 8 (men/women=4/4) (1.01%) were asymptomatic, while 4 (men/woman=3/1) (0.51%) had gait disturbance and/or dementia (possible iNPH). During a follow-up period of 4-8 years, two of the 8 asymptomatic subjects developed dementia and/or gait disturbance with worsening of ventriculomegaly on brain MRI in one case. The prevalence of possible iNPH was 0.51% (4/790) among Japanese elderly (>61 years of age). Asymptomatic ventriculomegaly with the iNPH features on MRI (AVIM) may represent a preclinical stage of iNPH.

[A case of neurofibromatosis type 2 (NF2) presenting with late-onset axonal polyneuropathy].

The patient was a 69-year-old man who had a two-year history of slowly-progressive gait disturbance, paresthesia of the distal legs and bilateral hearing impairment. Nerve conduction study showed symmetric motor-dominant axonal polyneuropathy of the legs. Gadolinium-enhanced brain and spinal cord MRI revealed bilateral vestibular schwannomas, and multiple small schwannomas in the cauda equina, the surface of spinal cord and lumbar muscles. Genetic examination disclosed a point mutation in the exon 2 (T161C: L54P) of the neurofibromatosis 2 (NF2) gene, and the diagnosis of NF2 was made. It has been reported that axonal polyneuropathy is frequently observed in patients with NF2. Therefore, it is possible that axonal polyneuropathy of the present patient may be due to the abnormality of the NF2 gene, but not to the direct compression of the tumors, because the localization of his schwannomas in the cauda equina and the spinal cord could not explain his symmetric polyneuropathy. Although this patient showed no characteristic clinical manifestations such as cutaneous lesions, gadolinium-enhanced brain and spinal cord MRI was useful for the detection of asymptomatic schwannomas. NF2 should be considered as a differential diagnosis in patients with axonal polyneuropathy, even if it is late-onset.

N-terminal region of alpha-synuclein is essential for the fatty acid-induced oligomerization of the molecules.

Exposure of alpha-synuclein (alphaS), a major component of Lewy bodies in Parkinson's disease, to polyunsaturated fatty acids (PUFAs) triggers the formation of soluble alphaS oligomers. Here, we demonstrate that PUFA binds recombinant alphaS protein through its N-terminal region (residues 2-60). In HEK293 cells, alphaS mutants lacking the N-terminal region failed to form oligomers in the presence of PUFA. The PUFA-induced alphaS oligomerization was accelerated by C-terminal truncation or Ser129 phosphorylation of alphaS; however, this effect was abolished by deletion of the N-terminus. The results indicate that the N-terminus of alphaS is essential for the PUFA-induced alphaS oligomerization.

Cerebral small vessel disease and C-reactive protein: results of a cross-sectional study in community-based Japanese elderly.

BACKGROUND AND PURPOSE: Inflammatory processes are involved in the pathogenesis of atherosclerosis. Inflammation has been known as a risk factor for coronary heart disease, whereas inflammation as a risk for cerebrovascular disease is less well established. Whether inflammatory processes, excluded from their involvement in large-vessel disease, are implicated in the pathogenesis of cerebral small vessel disease remains unclear. We assessed whether higher C-reactive protein (CRP) levels were associated with an increased number of lacunar infarcts or severity of white matter lesions. METHODS AND RESULTS: In a community-based group of Japanese elderly (n=689), CRP concentrations were measured using a highly sensitive assay. All participants underwent magnetic resonance imaging (MRI), and cerebral small vessel disease-related lesions (lacunar infarcts and white matter hyperintensity) were subsequently evaluated. Furthermore, carotid atherosclerosis was also assessed with ultrasonography. As the grades of white matter hyperintensity and the numbers of lacunes were considered small vessel disease-related lesions, we evaluated the relationships between CRP levels and small vessel disease-related brain lesions. Interestingly, the median CRP concentration of our participants was remarkably lower, being approximately one third or one quarter of the value of Western populations. Subjects with higher CRP levels tended to have more small vessel disease-related lesions; however, these associations were not seen after adjustment for cardiovascular risk factors and carotid atherosclerosis. CONCLUSIONS: The relationship between CRP levels and small vessel disease-related lesions was not apparent in the community-based Japanese elderly. The impact of inflammation in the pathogenesis of small vessel disease-related brain lesions seems to be weak among the Japanese elderly.

Cerebral small vessel disease and chronic kidney disease (CKD): results of a cross-sectional study in community-based Japanese elderly.

Chronic kidney disease (CKD) is known as a risk factor for cardiovascular disease. In recent years, several experimental and epidemiological studies have suggested that CKD is associated with endothelial dysfunction; thereby, a CKD state may initiate both large and small vessel damage. The association between renal dysfunction and asymptomatic lacunar infarction was reported in a hospital-based study, whereas the relationship between cerebral small vessel disease (SVD)-related lesions and CKD could not be clarified in a community-based study. We performed a cross-sectional study to determine the relationship between silent cerebral SVD-related lesions and CKD in a total of 625 community-based Japanese elderly. In this study, subjects with lower estimated glomerular filtration rate levels tended to have more lacunar infarcts and higher grades of white matter lesions (WMLs). In addition, the mean grades of WMLs or the mean numbers of lacunar infarction in the subjects with albuminuria were greater than those in subjects without albuminuria. In the logistic regression analysis, the association between the presence of CKD and lacunar infarction or moderate WMLs (Fazekas grades 2 and 3) was statistically significant (odds ratio [OR]: 1.86 and 1.50, respectively). Furthermore, as we performed additional analysis, excluding the subjects with stage 2 hypertension (those with casual blood pressure >or=160/100 mm Hg) or diabetes, CKD remained to be an independent risk for cerebral SVD-related lesions. This is the first study showing the relationship between silent SVD-related brain lesions and the presence of CKD, independently of conventional cardiovascular risk factors, in community-based elderly.

The role of G-protein-coupled receptor kinase 5 in pathogenesis of sporadic Parkinson's disease.

Sporadic Parkinson's disease (sPD) is a common neurodegenerative disorder, characterized by selective degeneration of dopaminergic neurons in the substantia nigra. Although the pathogenesis of the disease remains undetermined, phosphorylation of alpha-synuclein and its oligomer formation seem to play a key role. However, the protein kinase(s) involved in the phosphorylation in the pathogenesis of sPD has not been identified. Here, we found that G-protein-coupled receptor kinase 5 (GRK5) accumulated in Lewy bodies and colocalized with alpha-synuclein in the pathological structures of the brains of sPD patients. In cotransfected cells, GRK5 phosphorylated Ser-129 of alpha-synuclein at the plasma membrane and induced translocation of phosphorylated alpha-synuclein to the perikaryal area. GRK5-catalyzed phosphorylation also promoted the formation of soluble oligomers and aggregates of alpha-synuclein. Genetic association study revealed haplotypic association of the GRK5 gene with susceptibility to sPD. The haplotype contained two functional single-nucleotide polymorphisms, m22.1 and m24, in introns of the GRK5 gene, which bound to YY1 (Yin Yang-1) and CREB-1 (cAMP response element-binding protein 1), respectively, and increased transcriptional activity of the reporter gene. The results suggest that phosphorylation of alpha-synuclein by GRK5 plays a crucial role in the pathogenesis of sPD.

Microalbuminuria is a risk factor for cerebral small vessel disease in community-based elderly subjects.

Microalbuminuria (MA) is known as a marker for generalized vascular dysfunction. It occurs most commonly in the setting of diabetes and hypertension; however, its association with cerebral small vessel disease (SVD) in community-based elderly remains to be clarified. In this cross-sectional analysis, we evaluated the association between MA and cerebral SVD in total 651 community-based elderly subjects. We assessed cardiovascular risk factors by interviews and physical examinations, including an evaluation of urinary albumin creatinine ratio (UACR). All subjects underwent brain magnetic resonance imaging (MRI) and carotid ultrasonography. As endothelial markers, the serum levels of thrombomodulin (TM) and a tissue-type plasminogen activator/ plasminogen activator inhibitor-1 complex were also studied. The mean TM and UACR were higher in subjects with lacunar infarcts or with moderate white matter hyperintensities (mWMH) on MRI than in those without them. Additionally, the prevalence of lacunar infarcts or mWMH was higher in the highest tertile of UACR level than in the lowest or middle tertile. Furthermore, in logistic regression analysis, the elevation of logarithmically transformed UACR (log UACR) was associated with the higher likelihood for total lacunar infarcts (odds ratio [OR], 1.85 per one log UACR increase), multiple lacunar infarcts (OR, 1.89 per one log UACR increase), and mWMH (OR, 2.15 per one log UACR increase). The present study revealed that levels of urinary albumin are associated with cerebral SVD, independently of traditional cerebrovascular risk factors, in community-based elderly.

[A case of non-herpetic acute limbic encephalitis associated with a type-2 adenovirus infection].

This is a report of a 31-year-old woman with non-herpetic acute limbic encephalitis following a type-2 adenovirus infection. The patient was admitted to a hospital with high fever, severe liver dysfunction, and thrombocytopenia. Six days after admission, she became afebrile, and her liver dysfunction was normalized by conservative therapy. However, the patient started to experience generalized seizures that developed into status epileptics. The patient was then transferred to a referred hospital. Brain MR images revealed faint high-signal intensity in the bilateral limbic systems on FLAIR images. A CSF examination indicated mild pleocytosis. These findings suggested acute limbic encephalitis, which may have been mediated by an autoimmune reaction following some viral infection. Thus, steroid pulse therapy was started on the day of admission. The patient's condition, including the seizures and disturbances involving consciousness, improved gradually. The patient was discharged from the hospital in one month while still experiencing mild memory disturbances. Three months after onset of the illness, a T1-weighted MR image showed a linear high-signal intensity in the hippocampi, which indicated focal necrosis. Six months after onset, the patient's memory disturbance had been improved (her MMSE score was 28/30 points). We investigated the titers of many viruses that are known to cause liver dysfunction and found that a titer of the type-2 adenovirus was significantly elevated within three weeks. Although the anti-voltage-gated potassium channel (VGKC) antibody was not detected in the patient's serum, it seems that the autoimmune reaction after the type-2 adenovirus infection may have caused the acute limbic encephalitis.

[Trends in the incidence of stroke in Yamagata, Japan].

The purpose of this study was to clarify the incidence and features of acute cerebrovascular diseases in Yamagata Prefecture, by comparing with those in other prefectures reported in previous studies. Consecutive 13,639 cases of acute stroke were prospectively registered to Yamagata Society in Treatment for Cerebral Stroke (YSTCS) between January 1, 1998 and December 31, 2002. Cerebral infarction (CI), intracerebral hemorrhage (CH), subarachnoid hemorrhage (SAH) and transient ischemic attack (TIA) were observed in 58.4%, 25.8%, 11.4% and 4.4% of the patients, respectively. The frequencies of CH and SAH (37.2%) in Yamagata Prefecture were higher than those reported in other studies (p < 0.01). In addition, time from onset to admission in Yamagata Prefecture was longer than that reported in others(p< 0.01). This study was one of the largest stroke registration studies in Japan enrolling 13,639 patients. In addition, computed tomography (CT) and/or magnetic resonance image (MRI) was performed on admission in all patients. Diagnosis was made by a neurologist or a neurosurgeon based on CT and/or MRI findings. Our results might accurately reflect current status of stroke patients in Yamagata Prefecture.

[Abducens nerve palsy as the first manifestation of cavernous sinus sarcoidosis].

We report a 33-year-old man who presented with an acute onset of diplopia and orbitalgia. Neurological examination revealed right abducent nerve palsy. Brain MRI showed a gadolinium-enhancing mass lesion in the right cavernous sinus. Chest CT showed a small lymph node swelling in the subcarinal compartment. Serum angiotensin converting enzyme and lysozyme levels were within normal range. Biopsied lymph node in the left supraclavicular fossa showed non-caseating epitheloid granulomas, consistent with sarcoidosis. After oral administration of predonisolone, his right abducent nerve palsy ameliorated in a few days and completely disappeared by 6 weeks after treatment. Abducent nerve palsy can be the first clinical manifestation of cavernous sinus sarcoidosis.

[A case of methanol intoxication with optic neuropathy visualized on STIR sequence of MR images].

We report a 24-year-old man with severe methanol intoxication, who showed cerebral and optic nerve damages on MRI. He was admitted to our hospital with an acute onset of unconsciousness and severe metabolic acidosis, and was immediately treated by hemodialysis. His serum methanol concentration was 261.5 mg/dl. Although this methanol concentration was lethal, he was rescued by intensive care. Three days after admission, brain MRI was performed. Diffusion weighted images showed abnormal hyperintensities in bilateral putamina, subcortical white matter and cerebellar hemispheres. STIR sequence revealed bilateral optic nerve swelling with irregular hyperintense rims. These MRI features might reflect the optic nerve damages, mainly demyelination of the optic nerves caused by a myelinoclastic effect of formic acid, a metabolite of methanol.

A human granin-like neuroendocrine peptide precursor (proSAAS) immunoreactivity in tau inclusions of Alzheimer's disease and parkinsonism-dementia complex on Guam.

The deposition of tau inclusions is one of the neuropathological hallmarks in neurodegenerative disorders with dementia. We have reported that the N-terminal fragment of a human granin-like neuroendocrine peptide precursor (N-proSAAS) is accumulated in Pick bodies. However, it is unknown whether N-proSAAS is widely accumulated in tau inclusions in other tauopathies. Here, we performed an immunohistochemical examination using antibodies against both the N- and C-terminal sequence of proSAAS in the brains of patients with Alzheimer's disease and parkinsonism-dementia complex on Guam. The antibody against N-proSAAS immunostained neurofibrillary tangles and neuritic plaques in both diseases, whereas the antibody against the C-terminal sequence of proSAAS did not. The results of the present study suggest that N-proSAAS or proSAAS-like molecules were trapped within the tau fibrils and accumulated in tau inclusions.

Decreased galectin-1 immunoreactivity of the skin in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease involving motor neurons. In addition to motor neuron signs and symptoms, a lack of bedsores has been considered a feature of ALS. Recently, we revealed that galectin-1 is a component of the axonal spheroid, which is an early pathological change of the spinal cord in ALS. To investigate whether galectin-1 is associated with skin changes in ALS, we performed an immunohistochemical investigation using anti-galectin-1 antibodies. The present study revealed that galectin-1 immunoreactivity is reduced in the skin of patients with ALS, suggesting that cutaneous galectin-1 is involved in the pathological process of ALS.

Cerebrovascular disease in acute leukemia: a clinicopathological study of 14 patients.

OBJECTIVE: Cerebrovascular disease (CVD) is a serious complication of acute leukemia, and the underlying conditions are different from the common risk factors for CVD. The aim of this study was to characterize the clinical and pathological features of CVD in patients with acute leukemia. PATIENTS OR MATERIALS: In our series of 116 autopsied cases of acute leukemia during the period between January 1978 and December 1998, we had 14 patients who had CVD during the course of acute leukemia. The neuropathological and clinical features of those patients were examined. RESULTS: Neuropathological examination showed hemorrhagic infarction due to disseminated aspergillosis or mucormycosis (5 cases), multiple hemorrhages due to leukemic cell infiltration (2 cases) and a single massive hemorrhage with petechial hemorrhages in various regions of the brain (4 cases). Three patients had CVD due to miscellaneous causes. Clinicopathological correlation revealed that fungal disseminations occurred under agranulocytosis, while leukemic cell infiltration occurred under a marked leukocyotosis (peripheral white blood cell count >100,000/microl). Four patients with coagulopathy, including three with disseminated intravascular coagulation (DIC) had a single massive hemorrhage. CONCLUSION: Our study demonstrated that there were at least three types of CVD with specific clinicopathological features. Hemorrhagic infarction under agranulocyotosis was due to disseminated aspergillosis or mucormycosis. Multiple cerebral hemorrhages under marked leukocyotosis was due to leukemic cell infiltration into the brain. Massive cerebral hemorrhage was associated with coagulopathy including DIC.

Type 2 diabetes is not a risk factor for asymptomatic ischemic brain lesion--the Funagata study.

OBJECTIVE: The purpose of this study is to clarify whether type 2 diabetes (DM) is a risk factor for asymptomatic (silent) ischemic brain lesion, which is controversial at present. SUBJECTS AND METHODS: The subjects (n=187), who showed normal results on both neurological and neuropsychological examinations, underwent a 75-g OGTT and were examined by brain MRI on T1-weighted, T2-weighted, and FLAIR (fluid-attenuated inversion recovery) images. Their brain MRIs were evaluated quantitatively with the ischemia rating scale defined here. The subjects were grouped based on their glucose tolerance: normal glucose tolerance (NGT) (n=48), impaired glucose tolerance (IGT) (n=62), and DM (n=65). The subjects with DM were further divided based on their duration of illness: 20 with short duration (short DM: 1.3+0.8 years) and 45 with long duration (long DM; 8.9+/-5.4 years). Ages were matched among the groups. RESULTS: The percentages of individuals with asymptomatic ischemic brain lesion were 81% in NGT, 74% in IGT, 65% in short DM, and 78% in long DM. No significant difference was observed among the groups in terms of the percentage. Namely, even in individuals with a long history of DM without clinical stroke, the prevalence of asymptomatic ischemic brain lesion was not different from that of the other groups. Multiple regression and multiple logistic regression analyses showed that age and hypertension were significant independent risk factors for asymptomatic ischemic brain lesion, whereas hypercholesterolemia, smoking, and glucose intolerance, including IGT, short DM and long DM, were not. CONCLUSION: DM is not a risk factor for asymptomatic ischemic brain lesion.

Comparison of caregiver strain in Parkinson's disease between Yamagata, Japan, and Maryland, The United States.

BACKGROUND: Japan and the United States (US) have different cultures of caregiving including differences in family structure and social programs that may influence caregiver strain. Differences in caregiver strain between regions in Japan and in the US have not been investigated in patient-spouse dyads in PD. OBJECTIVES: To compare caregiver strain in spouses of PD patients between Yamagata, Japan and Maryland, US. Correlations between caregiver strain and patient/spousal variables are also examined. METHODS: In Yamagata and Maryland, spouses of patients with PD completed questionnaires assessing caregiver strain. Patients and spouses completed scales assessing mental health, and medical co-morbidity. PD severity and disability were assessed with the Unified Parkinson's Disease Rating Scale and the Schwab and England Activities of Daily Living Scale. Results in the two regions were compared with Chi-square and Student's t-tests. Relationships between caregiver strain and patient/spousal variables were analyzed with univariate correlations and multivariate regression. RESULTS: 178 Spouse-patient pairs were assessed. The level of caregiver strain in PD did not differ between Yamagata, Japan and Maryland, US despite differences in demographics and social support programs in the two regions. Yamagata spouses reported physical, time and financial constraints, while Maryland spouses reported more emotional distress. In both regions, spousal depression was a significant contributor to caregiver strain. CONCLUSION: Different approaches to reduce caregiver strain will likely be necessary in Yamagata and Maryland since the contributing factors to caregiver strain are influenced by differences in culture and social supports in each country.

[Case of acute limbic encephalitis associated with SLE accompanied with anti-glutamate receptor antibodies].

A 23-year-old woman was admitted to our hospital because of consciousness disturbance and convulsion, preceded by high fever, headache and erythema multiforme. Her brain magnetic resonance images showed hyperintense lesions in the left medial temporal lobe and the left pulvinar nucleus of the thalamus on fluid attenuated inversion recovery images. Analysis of cerebrospinal fluid showed mild pleocytosis, but DNA of herpes simplex or herpes type 6 viruses was negative on PCR. Laboratory investigations showed the presence of anti-nuclear antibodies, anti-RNP antibodies and lupus anticoagulant. The clinical diagnosis was made as acute limbic encephalitis associated with SLE, and subsequent administration of prednisolone improved her conditions. In her serum and cerebrospinal fluid, anti-glutamate receptor (ε2, δ2, ζ1) antibodies were detected, and the titers of the antibodies decreased as the symptoms improved. Although the mechanism underlying limbic encephalitis associated with SLE remains unclear, at least in some cases, the anti-glutamate antibodies may play an important role in the pathogenesis of limbic encephalitis with SLE.

A comprehensive study of repetitive transcranial magnetic stimulation in Parkinson's disease.

The clinical benefits of repetitive transcranial magnetic stimulation (rTMS) for Parkinson's disease (PD) remain controversial. We performed a comprehensive study to examine whether rTMS is a safe and effective treatment for PD. Twelve PD patients received rTMS once a week. The crossover study design consisted of 4-week sham rTMS followed by 4-week real rTMS. The Unified Parkinson's Disease Rating Scale (UPDRS), Modified Hoehn and Yahr Stage, Schwab and England ADL Scale, Actigraph, Mini-Mental State Examination, Hamilton Depression Scale, Wechsler Adult Intelligence Scale-revised, and cerebral blood flow (CBF) and cerebrospinal fluid (CSF) examinations were used to evaluate the rTMS effects. Under both drug-on and drug-off conditions, the real rTMS improved the UPDRS scores significantly, while the sham rTMS did not. There were no significant changes in the results of the neuropsychological tests, CBF and CSF. rTMS seems to be a safe and effective therapeutic option for PD patients, especially in a wearing-off state.